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1.
Toxins (Basel) ; 14(10)2022 Oct 13.
Article in English | MEDLINE | ID: mdl-36287972

ABSTRACT

Zearalenone (ZEN), also known as the F-2 toxin, is a common contaminant in cereal crops and livestock products. This experiment aimed to reveal the changes in the proteomics of ZEN-induced intestinal damage in weaned piglets by tandem mass spectrometry tags. Sixteen weaned piglets either received a basal diet or a basal diet supplemented with 3.0 mg/kg ZEN in a 32 d study. The results showed that the serum levels of ZEN, α-zearalenol, and ß-zearalenol were increased in weaned piglets exposed to ZEN (p < 0.05). Zearalenone exposure reduced apparent nutrient digestibility, increased intestinal permeability, and caused intestinal damage in weaned piglets. Meanwhile, a total of 174 differential proteins (DEPs) were identified between control and ZEN groups, with 60 up-regulated DEPs and 114 down-regulated DEPs (FC > 1.20 or <0.83, p < 0.05). Gene ontology analysis revealed that DEPs were mainly involved in substance transport and metabolism, gene expression, inflammatory, and oxidative stress. The Kyoto Encyclopedia of Genes and Genomes analysis revealed that DEPs were significantly enriched in 25 signaling pathways (p < 0.05), most of which were related to inflammation and amino acid metabolism. Our study provides valuable clues to elucidate the possible mechanism of ZEN-induced intestinal injury.


Subject(s)
Zearalenone , Animals , Swine , Zearalenone/analysis , Proteomics , Weaning , Amino Acids
2.
Anal Chim Acta ; 744: 75-81, 2012 Sep 26.
Article in English | MEDLINE | ID: mdl-22935377

ABSTRACT

A chemiluminescence (CL) array sensor for determination of benzenediol isomers simultaneously using the system of luminol-NaOH-H(2)O(2) based on a graphene-magnetite-molecularly imprinted polymer (GM-MIP) is described. Use of graphene in the GM-MIP thus prepared is helpful to improve the adsorption capacity, while use of magnetite nanoparticles can facilitate the isolation of GM-MIP at end of their synthesis, and rendering easier the use of the polymers in the array sensor. The adsorption performance and properties were characterized. The GM-MIP was used to increase the selectivity in CL analysis. In addition, the sensor was reusable and of good selectivity and adsorption capacity. The array sensor was finally used for the determination of hydroquinone, resorcinol and catechol in waste water samples simultaneously.


Subject(s)
Catechols/analysis , Ferrosoferric Oxide/chemistry , Graphite/chemistry , Hydroquinones/analysis , Luminescent Measurements/methods , Molecular Imprinting , Resorcinols/analysis , Adsorption , Hydrogen Peroxide/chemistry , Luminescent Measurements/instrumentation , Luminol/chemistry , Polymers/chemical synthesis , Polymers/chemistry , Sodium Hydroxide/chemistry , Surface Properties
3.
Talanta ; 98: 226-30, 2012 Aug 30.
Article in English | MEDLINE | ID: mdl-22939151

ABSTRACT

A new method for determination of L-tryptophan (L-try) using the flow injection chemiluminescence (FI-CL) system of KMnO(4)-SnCl(2)-CHOH based on a graphene oxide-magnetite-molecularly imprinted polymer (GM-MIP) is described. The L-try GM-MIP was synthesized using graphene oxide (G) which improved the adsorption capacity as carrier, and magnetite nanoparticles which made the polymers easier to use in the sensor. The adsorption performance and properties were characterized. The GM-MIP was used in CL analysis to increase the selectivity and the possible mechanism was also discussed. The CL sensor responded linearly to the concentration of L-try over the range from 2.10×10(-7) to 7.09×10(-4) M with a detection limit of 2.11×10(-8) M (3σ). The relative standard deviation (RSD) for the determination of 3.0×10(-5) M L-try was 2.40% (n=11). On the basis of speediness and sensitivity, the sensor is reusable and shows a great improvement in selectivity and adsorption capacity over other sensors. The sensor has been used for the determination of L-try in drug samples.


Subject(s)
Ferrosoferric Oxide/chemistry , Graphite/chemistry , Molecular Imprinting , Polymers/chemistry , Prescription Drugs/chemistry , Tryptophan/analysis , Adsorption , Flow Injection Analysis , Humans , Limit of Detection , Luminescence , Luminescent Measurements , Oxides , Potassium Permanganate/chemistry , Tin Compounds/chemistry
4.
Anal Bioanal Chem ; 404(1): 79-88, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22653423

ABSTRACT

This paper reports the preparation of dapsone (DDS) imprinted polymer layer-coated silica submicron particles (SiO(2)) combined with chemiluminescence (CL) toward analysis of tracing DDS in practical samples. To induce the selective occurrence of surface polymerization, the amino groups were first grafted at the surface of SiO(2) by the (3-aminopropyl)triethoxysilane (APTES). The molecularly imprinted polymers (MIP) were coated at the surface of modified SiO(2) by the graft copolymerization. After the removal of templates, recognition sites of DDS were exposed in the polymer layers. The DDS-imprinted products were characterized by FT-IR, SEM, TEM, dynamic adsorption, and static adsorption tests. The proximity between the thickness of MIP layer and the spatial size of DDS indicated that the imprinted sites almost situated at the surface of MIP, leading to rapid adsorption saturation within 90 min. The apparent maximum binding amount of MIP toward DDS was evaluated as 14.98 mg·g(-1), which was much higher than that of non-molecularly imprinted polymers. The CL sensor provided a wide linear range for DDS within 1.0 × 10(-6) to 1.0 × 10(-4) mol·L(-1) with a detection limit of 5.27 × 10(-7) mol·L(-1) and the relative standard deviation of 1.8 % (n = 11) by determinations of 5.0 × 10(-6) mol·L(-1) DDS. This method was applied to determine DDS in urine samples and satisfactory results were obtained.


Subject(s)
Anti-Bacterial Agents/analysis , Biosensing Techniques/methods , Dapsone/analysis , Flow Injection Analysis/methods , Polymers/chemistry , Adsorption , Anti-Bacterial Agents/urine , Biosensing Techniques/instrumentation , Dapsone/urine , Flow Injection Analysis/instrumentation , Luminescence , Molecular Imprinting , Polymers/chemical synthesis , Silicon Dioxide/chemistry , Urine/chemistry
5.
Bioresour Technol ; 114: 703-6, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22464421

ABSTRACT

A novel magnetic composite bioadsorbent composed of magnetic chitosan and graphene oxide (MCGO) was prepared as the magnetic adsorbent toward methylene blue. The magnetic composite bioadsorbent was characterized by SEM, FTIR and XRD measurements. The effect factors including pH, contact time and temperature on the adsorption properties of methylene blue onto MCGO were investigated. The resulting shows extraordinary adsorption capacity and fast adsorption rates for removal of methylene blue. The kinetics are well-described by pseudo-second-order kinetic. The experimental data of isotherm followed the Langmuir isotherm model and the Freundlich model, respectively. This work shows that the MCGO could be utilized as an efficient, magnetically separable adsorbent for the environmental cleanup.


Subject(s)
Chitosan/chemistry , Graphite/chemistry , Magnetite Nanoparticles/chemistry , Methylene Blue/chemistry , Methylene Blue/isolation & purification , Oxides/chemistry , Adsorption , Magnetite Nanoparticles/ultrastructure , Particle Size
6.
J Hazard Mater ; 215-216: 272-9, 2012 May 15.
Article in English | MEDLINE | ID: mdl-22429622

ABSTRACT

A novel magnetic composite bioadsorbent composed of magnetic chitosan and graphene oxide (MCGO) was prepared as the magnetic adsorbent. The morphology, chemical structure and magnetic property of the MCGO were characterized by Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD) and Scanning electronic microscope (SEM), respectively. Adsorption of methyl blue (MB) onto MCGO was investigated with respect to pH, adsorption time, initial MB concentration and temperature. Kinetics data and adsorption isotherm, obtained at the optimum pH 5.3, were better fitted by pseudo-second-order kinetic model and by Langmuir isotherm, respectively. The values of activation parameters such as free energy (ΔG, -0.74∼-1.46kJmol(-1)), enthalpy (ΔH, -10.28kJmol(-1)) and entropy (ΔS, -36.35Jmol(-1)K(-1)) were determined, respectively, indicating that the adsorption was spontaneous, favorable and exothermic process in nature. Moreover, the MCGO was stable and easily recovered, the adsorption capacity was about 90% of the initial saturation adsorption capacity after being used four times.


Subject(s)
Benzenesulfonates/chemistry , Chitosan/chemistry , Graphite/chemistry , Water Pollutants, Chemical/chemistry , Adsorption , Magnetics , Spectroscopy, Fourier Transform Infrared , Water Purification/methods , X-Ray Diffraction
7.
Colloids Surf B Biointerfaces ; 95: 42-9, 2012 Jun 15.
Article in English | MEDLINE | ID: mdl-22445236

ABSTRACT

The adsorption characteristics of hydroquinol from aqueous solutions onto the ß-cyclodextrin modified magnetic chitosan nanoparticles (CMCN) had been investigated. The characteristics results of FTIR, SEM and XRD showed that CMCN was successfully prepared. The influences of the pH of the solution and the contact time on the adsorption amounts had been discussed, and the appropriate process conditions for the adsorption of hydroquinol had been obtained. Equilibrium experiments fitted well with the Freundlich isotherm model, and the maximum adsorption capacity of the CMCN at 303 K was determined to be 1.75 mmol/g for hydroquinol at the concentration of 9.0 mmol/L, much higher than some conventional adsorbents. The CMCN was stable and easily recovered. Moreover, the adsorption capacity was about 90% of the initial saturation adsorption capacity after being used four times.


Subject(s)
Chitosan/chemistry , Chitosan/chemical synthesis , Hydroquinones/chemistry , Magnets/chemistry , Nanoparticles/chemistry , beta-Cyclodextrins/chemistry , Adsorption , Surface Properties
8.
Anal Chim Acta ; 718: 84-91, 2012 Mar 09.
Article in English | MEDLINE | ID: mdl-22305902

ABSTRACT

A novel flow injection chemiluminescence (FI-CL) sensor for determination of sulfadiazine (SDZ) using core-shell magnetic molecularly imprinted polymers (MMIPs) as recognition element is developed. Briefly, a hydrophilic MMIPs layer was produced at the surface of Fe(3)O(4)@SiO(2) magnetic nanoparticles (MNPs) via combination of molecular imprinting and reversible stimuli responsive hydrogel. And it provided the MMIPs with excellent adsorption capacity and rapid adsorption rate due to the imprinted sites mostly situated on the surface of MMIPs. Then the prepared SDZ-MMIPs were packed into flow cell to establish a novel FI-CL sensor. The sensor provided a wide linear range for SDZ of 4.0×10(-7) to 1.0×10(-4) mol L(-1) with a detection limit of 1.54×10(-7) mol L(-1). And the relative standard deviation (RSD) for the determination of 1.0×10(-6) mol L(-1) SDZ was 2.56% (n=11). The proposed method was applied to determine SDZ in urine samples and satisfactory results were obtained.


Subject(s)
Anti-Infective Agents/analysis , Flow Injection Analysis/instrumentation , Luminescent Measurements/instrumentation , Molecular Imprinting , Nanoparticles/chemistry , Sulfadiazine/analysis , Equipment Design , Flow Injection Analysis/methods , Limit of Detection , Luminescent Measurements/methods , Magnets/chemistry , Nanoparticles/ultrastructure , Polymers/chemistry
9.
Int J Biol Macromol ; 50(2): 444-50, 2012 Mar 01.
Article in English | MEDLINE | ID: mdl-22227306

ABSTRACT

A novel nano-adsorbent, ß-cyclodextrin-chitosan (CDC) modified Fe(3)O(4) nanoparticles (CDCM) is fabricated for removal of methyl blue (MB) from aqueous solution by grafting CDC onto the magnetite surface. The characteristics results of FTIR, SEM and XRD show that CDC is grafted onto Fe(3)O(4) nanoparticles. The grafted CDC on the Fe(3)O(4) nanoparticles contributes to an enhancement of the adsorption capacity because of the strong abilities of CDCM, which includes the multiple hydroxyl, carboxyl groups, amino groups and the formation of an inclusion complex due to the ß-CD molecules through host-guest interactions, to adsorb MB. The adsorption of MB onto CDCM is found to be dependent on pH and temperature. Adsorption equilibrium is achieved in 50 min and the adsorption kinetics of MB is found to follow a pseudo-second-order kinetic model. Equilibrium data for MB adsorption are fitted well by Langmuir isotherm model. The maximum adsorption capacity for MB is estimated to be 2.78 g/g at 30°C. The CDCM was stable and easily recovered. Moreover the adsorption capacity was about 90% of the initial saturation adsorption capacity after being used four times.


Subject(s)
Benzenesulfonates/chemistry , Chitosan/chemistry , Magnets , Metal Nanoparticles/chemistry , beta-Cyclodextrins/chemistry , Adsorption , Chitosan/chemical synthesis , Hydrogen-Ion Concentration , Kinetics , Metal Nanoparticles/ultrastructure , Temperature , Thermodynamics , beta-Cyclodextrins/chemical synthesis
10.
Colloids Surf B Biointerfaces ; 91: 250-7, 2012 Mar 01.
Article in English | MEDLINE | ID: mdl-22119217

ABSTRACT

A novel, chitosan coating on the surface of magnetite (Fe(3)O(4)) (MIMC) was successfully synthesized using alizarin red (AR) as a template for adsorption and removal of AR from aqueous solutions. Characterization of the obtained MIMC was achieved by FTIR spectra, SEM micrographs and XRD. Batch adsorption experiments were performed to investigate the adsorption conditions, selectivity and reusability. The results showed that the maximum adsorption capacity was 40.12 mg/g, observed at pH 3 and temperature 30°C. Equilibrium adsorption was achieved within 50 min. The kinetic data, obtained at the optimum pH 3, could be fitted with a pseudo-second-order equation. Adsorption process could be well described by Langmuir adsorption isotherms and the maximum adsorption capacity was calculated as 43.08 mg/g. The selectivity coefficient of AR and other dyes onto MIMC indicated an overall preference for AR, which was much higher than non-imprinted magnetic chitosan beads. Moreover, the sorbent represented high stability and good repeatability.


Subject(s)
Anthraquinones/isolation & purification , Water Pollutants, Chemical/isolation & purification , Adsorption , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Spectroscopy, Fourier Transform Infrared , Temperature , X-Ray Diffraction
11.
Article in English | MEDLINE | ID: mdl-22112574

ABSTRACT

A novel molecular imprinting-chemiluminescence (MIP-CL) sensor for the determination of L-phenylalanine (Phe) using molecularly imprinted polymer (MIP) as recognition element is reported. The Phe-MIP was synthesized using acrylamide (AM) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as cross-linker, 2,2-azobisisobutyronitrile (AIBN) as initiator and the polymers' properties were characterized. Then the synthesized MIP was employed as recognition element by packing into flow cell to establish a novel flow injection CL sensor. The CL intensity responded linearly to the concentration of Phe in the range 1.3 × 10(-6) to 5.44 × 10(-4) mol/L with a detection limit of 6.23 × 10(-7) mol/L (3σ), which is lower than that of conventional methods. The sensor is reusable and has a great improvement in sensitivity and selectivity for CL analysis. As a result, the new MIP-CL sensor had been successfully applied to the determination of Phe in samples.


Subject(s)
Luminescence , Microspheres , Molecular Imprinting/methods , Online Systems , Phenylalanine/analysis , Polymers/chemistry , Animals , Biosensing Techniques , Flow Injection Analysis , Microscopy, Electron, Scanning , Milk/chemistry , Phenylalanine/chemistry , Recycling , Regression Analysis , Spectrophotometry, Infrared
12.
J Hazard Mater ; 194: 193-201, 2011 Oct 30.
Article in English | MEDLINE | ID: mdl-21889845

ABSTRACT

A novel, thiourea-chitosan coating on the surface of magnetite (Fe(3)O(4)) (Ag-TCM) was successfully synthesized using Ag(I) as imprinted ions for adsorption and removal of Ag(I) ions from aqueous solutions. The thermal stability, chemical structure and magnetic property of the Ag-TCM were characterized by the scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR) and vibrating sample magnetometer (VSM), respectively. Batch adsorption experiments were performed to evaluate the adsorption conditions, selectivity and reusability. The results showed that the maximum adsorption capacity was 4.93 mmol/g, observed at pH 5 and temperature 30°C. Equilibrium adsorption was achieved within 50 min. The kinetic data, obtained at the optimum pH 5, could be fitted with a pseudo-second order equation. Adsorption process could be well described by Langmuir adsorption isotherms and the maximum adsorption capacity calculated from Langmuir equation was 5.29 mmol/g. The selectivity coefficient of Ag(I) ions and other metal cations onto Ag-TCM indicated an overall preference for Ag(I) ions, which was much higher than non-imprinted thiourea-chitosan beads. Moreover, the sorbent was stable and easily recovered, the adsorption capacity was about 90% of the initial saturation adsorption capacity after being used five times.


Subject(s)
Chitosan/chemistry , Magnetics , Silver/isolation & purification , Water/chemistry , Adsorption , Hydrogen-Ion Concentration , Kinetics , Microscopy, Electron, Scanning , Temperature , X-Ray Diffraction
13.
Colloids Surf B Biointerfaces ; 88(2): 574-81, 2011 Dec 01.
Article in English | MEDLINE | ID: mdl-21868204

ABSTRACT

The performance of a cross-linked magnetic modified chitosan (CMMC), which has been coated with magnetic fluids and cross-linked with glutaraldehyde, has been investigated for the adsorption of Zn(2+) from aqueous solutions. The CMMC with a diameter range of 20-50 nm was prepared. The effects of pH and the contact time for the adsorption have been discussed, and the optimal adsorption conditions for the adsorption of Zn(2+) have been obtained. The research results showed that CMMC was highly efficient for fast adsorption of Zn(2+) within the first 25 min, and adsorption equilibrium could be achieved in 30 min. Equilibrium studies showed that the data of Zn(2+) adsorption followed the Langmuir model. The maximum adsorption capacity for Zn(2+) was estimated to be 32.16 mg/g with a Langmuir adsorption equilibrium constant of 0.01 L/mg at 298 K, which demonstrated that the CMMC had obvious efficient adsorption of Zn(2+). The CMMC was stable and easily recovered. Moreover, the adsorption rate was about 90% of the initial saturation adsorption capacity after being used five times.


Subject(s)
Chitosan/chemistry , Magnetics , Water/chemistry , Zinc/chemistry , Adsorption , Hydrogen-Ion Concentration , Molecular Structure
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